Adjustable ground rail connecter



Jan. 19, 1937. c. R. ANDERSON Y 2,063,523

'- ADJUSTABLE GROUND RAIL CONNEGTER Filed Oct. 15, 1935 2 4 INVENTOR 25 dafl Patented Jan. 19, 1937 UNITED STATES PATENT OFFICE The Martin-Hardsocg Company,

Pittsburgh,

Pa., a corporation of Pennsylvania Application October 15, 1935, Serial No. 45,095

8 Claims.

This invention pertains to electrical connecters and, more particularly, to an electrical connecter for use in making a connection to a rail for the ground side of a circuit.

Connecters of the type to which the present invention relates are largely used in mines where certain parts of the main track system are electrified, but where the tracks immediately adjacent the working faces of the rooms are not electrified. The mining machines, which are mobile, are electrically driven. They are provided with an electric cable. One wire in this cable is provided with a connecter adapted to engage the trolley side of the electrified track circuit and the other wire of the cable is clamped to one of the rails of the electrified track circuit. Heretofore clamps provided for making connection to the rail have been such that good contact with the rails is not at all times secured,

, resulting in the irregular operation ofthe mining machine and unnecessary heating of the motors. Moreover, the use of such clamps as have heretofore been provided has been attended with considerable inconvenience. Clamps of this type are also used in other places where one side of a circuit has to be connected to a rail of an electric track system, the use not being confined entirely to mines and mining machinery.

According to the present invention, there is provided an adjustable clamping connecter of simple construction which can be easily operated and which is adaptable for rails over a wide range of sizes. The invention contemplates the provision of a body member having a claw for engagement with one flange of a rail and having a slide member movable therealong having a rail-clamping element supported therein with an actuating means for the rail-clamping element, the arrangement being such that when one flange of the rail is engaged by the fixed claw, the slide member may be moved toward the other flange, and when engaged with the other flange moved into clamping engagement therewith and at the same time the sliding member be clamped against free movement along the body on which it is carried. I

The invention may be readily understood by reference to the accompanying drawing, in which Figure 1 represents a side elevation of a grounding clamp connecter embodying my invention;

Figure 2 is a top plan view of the connecter shown in Fi e 1;

Figure 3 is a perspective view of the movable contact jaw;

Figure 4 is a perspective view of the slide member in which the movable contact jaw is mounted;

Figure 5 represents a transverse section in the plane of line V-V of Figure 1; and

Figure 6 is a view partly in elevation and partly in section of a modified arrangement.

Referring to the drawing, 2 designates a body member of conducting material, preferably copper, this body member being in the form of an elongated bar having a fixed claw 3 at its outer end. The claw member 3 is bent over at an acute angle so as to provide a tapering space between the underside of the claw on the top of the body 2 to receive one flange of a rail, as clearly shown in Figure 1. In Figure 1, the outline of a rail is indicated in dotted lines, and the manner in which the sloping flange of the rail is engaged under the claw 3 is clearly indicated.

Mounted on the bar or body 2 and slidable therealong is a slide member 4, this member having an undercut guideway 5 therein to receive and engage the bar 2 and having upstanding side flanges 6. This slide member has a forwardly projecting extension or lip portion 1.

Pivotally supported between side member 6 of the slide is a jaw member 8 having a forwardly extending rail flange engaging portion 8a and having a rearwardly projecting lip portion 9. It will be noted that the under surface of the jaw portion 8a is tapered. This taper allows the jaw to accommodate itself to rails of different sizes, running from 25-110. to 50-lb. rails and even heavier. It is, of course, important that there be good contact with the rail over a relatively large surface whether the rail be a small rail or a large one. The pivoted jaw member 8 also has a rearwardly extending lug IE1 spaced below the rearwardly projecting extension 9. A pin ll serves to provide the pivotal support for the member 8. The jaw member has a slightly curved bottom surface to which may, but which does not necessarily, rest on the top of the bar 2.

Pivotally supported in the slide member to the rear of the jaw 8 is an actuating member designated generally as l2. This actuating member has a cam portion [3 which engages under the lip or extension 9 on the jaw, and has a nose portion I4 positioned over the lug ill. The member I2 is provided with an operating handle l5 having an insulating sleeve thereon. The member I2 is pivotally supported by means of a pin [1.

Bolted to the bar 2 is a lateral extension or connecter member it! having a clamp I9 thereon with a bolt for adjusting the clamp, this clamp being for engaging the terminal of the cable 2| leading to the mining machine or other machine to be connected with the rail. The bar 2 has a rearwardly extending portion back of the connecter designated 22, the extension 22 being covered with an insulating sleeve 23. This forms a handie for the connecter unit.

It will be noted that the portion 8a. of the jaw is of a width greater than the width between the two upstanding flanges 6-6 so as to afford an increased area of contact with the rail flange. It will also be noted that this part of the jaw member overhangs the forwardly projecting lip or extension 7 on the slide 5.

In the use of the device the cable 2| is firmly attached to the clamp |8|9 so as to make a substantially permanent connection. The connecter is then hooked onto the track rail by bringing the overhanging claw 3 against one flange of the rail and pulling it up tightly against the rail. The operator, holding handle |5I6 in the position shown in Fig. 1 then slides the slide forwardly as far as it will go to engage the other flange of the rail. Downward pressure is then applied to the handle |5--|6, and the movement of the cam !3 under the overhanging lip 9 causes the jaw to be rocked in such manner that the lip portion 8a thereof is pressed firmly against the flange of the rail. Upon release of pressure from the handle |5|6, the member remains clamped to the rail. When it is desired to release the clamp, the handle |5-|5 is lifted up, relieving the pressure from the under surface of the rearward extension 9. Further continued upward movement of the handle causes the nose I4 to press down against the lug iii, exerting a lifting movement to the jaw, so that the portion 8a will be forced out of contact with the flange of the rail. The slide can then be easily retracted and the connecter released from engagement with the rail.

The device does not require the use of any springs and the clamping pressure exerted by the jaw is always exerted against the flange of the rail, tending to pull the slide member 4 against the bottom of the bar 2. There are no contact points where the pressure is localized against the bar 2, so that the bar 2, if it be made of copper or other relatively soft conducting material, is not dented or mutilated in the operation of clamping the connecter to the rail.

The arrangement shown in Figure 6 shows a generally similar device but wherein the jaw member is provided with gear teeth to engage corresponding gear teeth on the operating member. In this figure 24 designates a body member in all respects similar to the body member 2 previously described and, therefore, only a small portion of the body member 24 is shown in Figure 6. 25 designates a slide member movable along the bar or body 24 and constructed similarly to the slide member l shown in Figure 4. This slide member 25 has upwardly extending side members 26 similar to the side members 6 of the member shown in Figure 4. The jaw 2'? is generally similar to the jaw member 8 of Figure 3, having a forwardly extending lip portion for engagement with the flange of the rail, this lip portion being designated 21a and being widened outin the same manner that the jaw member previously described is widened. It has a portion 28 disposed between the two side plates 26 through which the pivot pin 29 passes, and rearwardly of the pivot pin the portion 28 is provided with an arcuately disposed series of gear teeth 30. Supported on a pin 3| between side members 26 is the operating member designated generally as 32 and having an insulated handle 33. The operating member has a forwardly extending portion 34 with gear teeth 35 arranged to cooperate with the gear teeth 30. When the handle 33 is pressed down, the motion transmitted through the gear teeth to the jaw member 2! is such as to cause the lip 21a to be forced down against the flange of the rail, whereas movement of the handle in the opposite direction causes the jaw member to be lifted out of engagement with the flange of the rail. It will be seen in this arrangement as in the arrangement previously described, that the motion of the handle is positively transmitted to the clamping element and that the clamping element acts directly against the flange of the rail, no local pressure being exerted at any point against the body 24. In either of the forms of devices just described, the arrangement is such that when the operator grasps the handle IE5 or 33 to move the clamping element toward the flange of the rail the jaw is opened, thus facilitating the application of the connecter to the rail. Likewise, in either form, the application of downward pressure on the handle forces the jaw into rail-clamping position. Either form of the device provides a very simple and eifective clamp which can be used with rails of a wide variety of sizes and wherein contact with relatively wide surfaces of the rail is assured, so that even though the rail might be slightly rusty, nevertheless, a good connection will be made.

While I have shown and described certain preferred embodiments of my invention, it will be understood that various changes and modifications may be made within the contemplation of my invention and under the scope of the following claims.

I claim:

1. A ground rail connecter clamp comprising a bar-like body member having a rail flange engaging claw at one end thereof, a slide member having a guideway therein in which guideway the bar-like body member is received and in which said body member has a sliding fit, and. an adjustable jaw element on the slide member mounted for movement about a fixed point on the slide and movable vertically into and out of clamping engagement with the flange of a rail engaged by the connecter.

2. A ground rail connecter clamp comprising a bar-like body member having a rail flange engaging claw at one end thereof, a slide member on the body member, said slide member having a guideway therethrough to receive the body member, said slide member having upstanding side portions, a movable jaw member pivotally supported between said upstanding side portions, and operating means for said jaw.

3. A ground rail connecter clamp comprising a bar-like body member having a rail flange engaging claw at one end thereof, a slide member mounted on the body member for movement longitudinally thereof, a rail flange engaging jaw member pivotally supported on the slide memher, and operating means for the jaw pivotally mounted on the slide member.

4. A ground rail connecter clamp comprising a bar-like body member having a rail flange engaging claw at one end thereof, a slide member mounted on the body member for movement longitudinally thereof, a rail flange engaging jaw member pivotally supported on the slide member and having a rearwardly extending operating extension, and an operating member pivotally supported in the slide member having motion transmitting means thereon cooperating with the rearwardly extending portion of the jaw member for transmitting motion thereto.

5. A ground rail connecter clamp comprising a bar-like body member having a rail flange engaging claw at one end thereof, a slide member mounted on the body member for movement longitudinally thereof, a rail flange engaging jaw member pivotally supported on the slide member and having a rearwardly extending portion with projections thereon, an operating handle pivotally supported on the slide member, said operating handle having a forwardly extending portion with projections thereon interfltting with the projections on the rearwardly extending portion of the jaw whereby movement of the handle downwardly causes a downward movement of the jaw and an upward movement of the handle effects an upward movement of the jaw.

6. A ground rail connecter clamp comprising a bar-like body member, having a rail flange engaging claw at one end thereof, a slide member movable along the body member, an operating handle pivotally supported on the sliding member, a rail flange engaging jaw member also pivotally supported on the slide member, and cooperating means on the handle member and jaw member for transmitting motion from the handle member to the jaw member.

7. A ground rail connecter clamp comprising a bar-like body member having a rail flange engaging claw at one end thereof, a slide member movable along the body member and having a sliding fit thereon, a movable jaw member on the slide member movable vertically into and out of engagement with the flange of a rail to be engaged by the clamp, operating means on the slide member, and means operatively connecting the operating means and the jaw for positively transmitting motion in two directions from the handle member to the jaw member.

8. A ground rail connecter clamp comprising a bar-like body member having a rail flange engaging claw at one end thereof, a slide member movable along the body member and having a sliding fit thereon, a movable jaw member on the slide member movable vertically into and out of engagement with the flange of a rail to be engaged by the clamp, operating means on the slide member, and means operatively connecting the operating means and the jaw for positively transmitting motion in two directions from the handle member to the jaw member, said last named means including a cam on the handle member cooperating with the cam-engaging surface on the jaw member, the cam being movable to an over-center position whereby pressure on the jaw will not efiect movement of the handle member.

CECIL R. ANDERSON. 

